1. Field
An aspect of the present disclosure relates to a touch screen panel.
2. Description of the Related Art
There are known various methods of implementing touch screen panels, including a resistive layer method, an optical sensing method, and an electrostatic capacitance method. A touch screen panel using the electrostatic capacitance method includes a plurality of sensing electrodes, and senses changes in capacitance formed in the sensing electrodes when a user's finger or stylus pen comes in contact with the sensing electrodes, thereby detecting a touch position.
Specifically, the touch screen panel may include sensing electrodes, a touch driver, and a charge pump circuit. The touch driver generates touch driving signals by using an output voltage supplied from the charge pump circuit, and applies the touch driving signals to the sensing electrodes. The touch screen panel senses changes in capacitance by sensing touch sensing signals corresponding to the touch driving signals.
However, the touch screen panel is influenced by power noise due to driving of the charge pump circuit. Specifically, a noise is generated corresponding to a change in voltage in the charge pump circuit. The generated noise changes capacitance between the sensing electrodes, and therefore, a touch error may occur.
In a conventional touch screen panel, a charge pump circuit and a touch driver are asynchronously driven, and therefore, the influence of power noise is aperiodically generated based on touch driving timing. As touch screen panels become large in size, touch drivers are driven at a high voltage so as to obtain a high signal-to-noise ratio (SNR). Hence, the influence of power noise increases. Accordingly, a plan for reducing power noise is required.